Coated electrical conductors may comprise one or more electrical insulation layers formed around a conductive core. Magnet wire is one form of coated electrical conductor in which the conductive core is a copper wire, and the insulation layer or layers comprise dielectric materials, such as polymeric resins. Magnet wire is used in the electromagnet windings of transformers, electric motors, and the like. Because of its use in such windings, friction, and abrading forces are often encountered. As a result, this insulation layer can be susceptible to damage.
High voltage-surge failure rate, for example, has been of concern to motor manufacturers. Surge failure is associated with insulation damage resulting from modern, fast automatic winding and abusive coil insertion processes for motor stators. Coating a polyester insulated wire with an abrasion resistant polyamideimide and wax is one way to minimize friction thereby reducing wire surface damage during the winding process. Wires manufactured in this manner, however, can experience surge failure rates of at least about 10,0000-20,0000 parts per million. Another form of failure is varnish craze. Varnish craze is a small fissure (about 1-2 microns deep) on the surface of the coating. Typically, varnish craze includes several fissures in a localized area that impair the insulative properties of the wire. Therefore, a need exists for a wire coating that will offer high resistance to the various damaging effects to wire coatings, including abrasion, and varnish craze.